How a haircut changed the world: The Beatles create the moptop

But in 1961, fifty years ago this month, they'd lose those quiffs, brush their hair forward and become the "lovable mop-tops" of early myth. Paul McCartney would later say that this was crucial for their success, particularly in America. "We came out of nowhere with funny hair, looking like marionettes or something," he said. "That was very influential. I think that was really one of the big things that broke us - the hairdo more than the music, originally."

But it didn't just break them, it changed the world.

The origins of the cut go back to The Beatles early years playing gigs in Hamburg. They met a young German art student, Jurgen Vollmer, who always wore his hair brushed forward in a style that the Germans called "pilzkopf" or "mushroom head". At that time their idea of Germans had been formed by the war comics they read and old news reel footage of Nazis. They were surprised to find that Germans like Jurgen and Astrid Kirchherr were cool, arty and much more sophisticated than most of their friends back in Liverpool. They admired Jurgen's art and, crucially, they admired his hair.

John and Paul bumped into Jurgen again in the autumn of 1961 on a hitchhiking trip to Paris and they persuaded him to hack their hair into a similar style. When they got back to Liverpool George and later Ringo enthusiastically followed suit.

How did it go down?

In the UK this style caused a few amused comments but, by now smartly dressed in tailored suits by their manager Brian Epstein, they'd had their more rebellious edges carefully softened. It was when they reached America that their hair caused a scandal made up of equal parts amusement, shock, disapproval and delight.

"One shake of the bushy fringe of their moplike haircuts is enough to start a riot in any theatre where they are appearing," said the New York Times.

However, any sense that they were a threat to society was soon squashed by their friendliness and wit. "What do you call your hairstyle?" George was asked.

"Arthur," he replied.

From then on crew cuts and even quiffs seemed deeply dated. The "mop-tops" as they were soon dubbed in the States made long, "rebellious" hair cuddly and cute. It was an open door for the hippies to march right through. Not many years later they would become hippies themselves and they would start to feel embarrassed about the cuddly image of their early days. They'd sold their original dream of being cool, moody rock 'n' roll stars to become walking, talking action dolls.

If they hadn't done so, though, would the 60s have played out the same? It's hard to imagine The Rolling Stones would have had such a positive reception in the States if "Arthur" hadn't gone first. The establishment couldn't lay a finger on The Beatles because they'd already charmed the world. When they finally revealed their true colours and started talking about drugs, sex and political change it was too late to stop them.